Fig. 1.

Box and whisker plots of preoperative and peak postoperative plasma B-type natriuretic peptide (BNP) concentrations for 1,025 subjects undergoing primary coronary artery bypass graft surgery. BNP concentrations are stratified by the group of 920 subjects who did not experience heart failure (HF) events and the group of 105 subjects who did experience HF events during 5-yr postoperative follow-up. The 10th (lower whisker), 25th (lower box end), 50th (middle line), 75th (upper box end), and 90th (upper whisker) percentile BNP values are shown for each group for both the preoperative and peak postoperative (postoperative days 1–5) assessments. *P < 0.001 HF event compared with the no-HF event group at that perioperative time point.